Fossil Keticulate Sponges. 473 



The fragment has a length of 60 mm., the distance between the 

 rows of nodes is 12 mm. 



It differs from D. tuberosum in having the longitudinal rows of 

 nodes more nearly parallel, smaller, and more closely arranged in rows 

 while they are not angular. 



Formation and locality. In an argillaceous sandstone of the Che- 

 mung group; Steuben county, IN. Y. 



DICTYOPHYTON TUBEROSUM. 

 Plate 18, Figs. 7, 8. 



Eydnoceras tuberosum, Conrad. Jour. Nat. Sci. Phil., vol. viii, p. 267, pi. 16, 



fig. 1. 1842. 

 Dictyophyton tuberosum (Conrad), Hall. Sixteenth Rept. State Cab. Nat. 



Hist., p. 90, pi. 3, fig. 1. 1863. 

 Not Dictyophyton tuberosum (Conrad), Barrois. Memoire sur les Dictyo- 



spongidse; Ex. des Ann. de la Soc. Geol. du Nord, t. xi, p. 82, pi. 1, fig. 



1. 1883. 



Cup turbinate, elongate, more or less expanded above, attenuate 

 below. 



Surface ornamented by strong elevated nodes, which are arranged 

 m regular order longitudinally and transversely. The transverse 

 ranges are in four pairs, making eight nodes in the circumference. 

 The intermediate spaces are concave and the interval between each 

 row is also broadly concave. The nodes are themselves elongate -coni- 

 cal, often becoming compressed and subcuneate afr the extremity. 

 Entire surface reticulate with longitudinal and transverse striae which 

 are continued over the nodes. In well-preserved specimens the. fas- 

 cicles in the line of the nodes are- extended into longitudinal ele- 

 vated lamellae, which are produced into spiniform extensions of the 

 crests of the nodes. 



Specimens vary in length from 150 to 250 muic, and in diameter at 

 the largest end from 25 to 130 mm. or more. 



Formation and localities. In the upper part of the Chemung 

 group ; in Howard, Addison and Cohocton, Steuben county, NT. Y. 



Dictyophyton sacculum, n. sp. 



Dictyophyton Redjieldi? Hall. Sixteenth Rept. State Cab. Nat. Hist., pi. 4, 



fig. 6. 1863. 



Cup cylindrical, short ; length once and a.half the width in a com- 

 pressed specimen. 



Surface coarsely reticulate, without nodes, the larger striae not being 

 very conspicuous. 



The compressed specimen has a length of 33 mm. and a width in 

 the middle of 20 mm. 



In the original publication this species was referred with doubt to 

 D. Redjieldi, but a critical examination shows it to be entirely distinct. 

 The specimen is probably incomplete. 



[Sen. Doc. No- 38.] 60 



